Intrauterine device

ABSTRACT

An intrauterine device composite is provided which comprises a plastic matrix, such as a copolymer of ethylene and vinyl acetate, having a particulate material selected from the group consisting of metals such as copper, zinc, silver, platinum, or cadmium, and metal salts dispersed within the matrix. The particulate preferably includes both a metal and a salt, such as a sulfate, thereof, although solely a salt or a metal particulate may be utilized. In addition, a radio-opaque particulate such as barium sulfate is preferably also dispersed within the composite. The particulate material preferably comprises between 0.1% to 50% by weight of the composite, and the matrix preferably has a water permeability or rate of water vapor transmission of at least 0.3 grams/100 square inches/24 hours/mil at 25* C.

United States Patent [191 Lerner et a1.

[ INTRAUTERINE DEVICE [75] Inventors: Irwin S. Lerner, Greenwich, Conn;

Hugh J. Davis, Baltimore, Md.; Thad J. Earl, Defiance, Ohio [73]Assignee: A. H. Robins Company,

Incorporated, Richmond, Va.

[22] Filed: Feb. 26, 1973 [21] Appl. No.: 336,066

Related US. Application Data [63] Continuation of Ser. No. 88,538, Nov.12, 1970,

abandoned.

[52] US. Cl. 128/130, 424/ 14 [51] Int. Cl. A61f 5/46 [58] Field ofSearch 128/130, 131; 424/14, 16, 424/22 [56] References Cited UNITEDSTATES PATENTS 3,306,286 2/1967 Ahmed .Q. 128/130 3,563,235 2/1971Zipper 128/130 3,633,574 l/l972 Lerner 128/130 Sept. 10, 1974 PrimaryExaminer-Richard A. Gaudet Assistant Examiner-G. F. Dunne Attorney,Agent, or FirmStrauch, Nolan, Neale, Nies & Kurz [5 7] ABSTRACT Anintrauterine device composite is provided which comprises a plasticmatrix, such as a copolymer of ethylene and vinyl acetate, having aparticulate material selected from the group consisting of metals suchas copper, zinc, silver, platinum, or cadmium, and metal salts dispersedwithin the matrix. The particulate preferably includes both a metal anda salt, such as a sulfate, thereof, although solely a salt or a metalparticulate may be utilized. In addition, a radio-opaque particulatesuch as barium sulfate is preferably also dispersed within thecomposite. The particulate material preferably comprises between 0.1% to50% by weight of the composite, and the matrix preferably has a waterpermeability or rate of water vapor transmission of at least 0.3grams/100 square inches/24 hours/mil at 25 C.

17 Claims, 1 Drawing Figure PATENTEDSEFTOIQN v 3.334.373

, INVENTORS IRWIN S. LERNER HUGH J. DAVIS THAD J. EARL ATTORNEYS.

INTRAUTERINE'DEVICE CROSS REFERENCE TO RELATED APPLICATION Thisapplication is a continuation of application Ser. No. 88,538 filed Nov.12, 1970 and now abandoned.

BACKGROUND OF THE INVENTION l. Field of the Invention The presentinvention relates to intrauterine device composites and moreparticularly to such composites comprising a plastic matrix having aparticulate material dispersed therein.

2. Description of the Prior Art Prior art intrauterine devices haveutilized structures including a metal wire in order to obtain improvedresults. Such prior art devices have involved the use of a plasticT-shaped device having a fine copper wire wrapped about the upper end ofthe stem of the T, a silkworm gut wrapped in a bronze wire,- and acopper loop having a silkworm gut tail. These prior art intrauterinedevices, however, are bulky, difficult to insert, and are notnecessarily well tolerated within the uterine cavity. Moreover, wheneverany beneficial effect has been observed, a substantial quantity of timehas been required before such beneficial effects occur, resulting in alag time between insertion of the device and achievement of the benefitsthereof. In addition, in intrauterine devices employing a'wire wrappedabout a T-stem, the wire tends to dissolve and break up thus minimizingits long range effectiveness. Furthermore, such prior art devices have arelatively low surface area for the metal which, thereby, also minimizestheir effectiveness. Due to these disadvantages, prior art intrauterinedevices have not achieved the wide spread usage enjoyed by oralcontraceptives. The present invention overcomes these disadvantages ofthe prior art.

SUMMARY OF THE INVENTION An intrauterine device composite is providedwhich comprises a plastic matrix having a particulate material dispersedwithin the matrix. The particulate material is selected from the groupconsisting of metals and metal salts and comprises between 0.1% and 50%by weight of the composite. The particulate preferably includes both ametal and a salt, such as a sulfate thereof, although solely a metal ora salt particulate may be utilized. In addition, a radio-opaqueparticulate, such as barium sulfate, is preferably also dispersed withinthe matrix. The plastic matrix preferably has a water permeability orrate of water vapor transmission of at least 0.3 grams/ 100 squareinches/24 hours/mil at 25 C.

BREIF DESCRIPTION OF THE DRAWING The FIGURE is a diagrammaticillustration exemplary of an intrauterine device composite in accordancewith the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT shown. The shielddevice 10 disclosed in co-pending application, Ser. No. 775,729,preferably has a contour which conforms to the mid-range of the uterinecavity, and has a plurality of lateral fins 1212 which promote retentionand permit accommodation to uterine contractions and variations inuterine shape extending outwardly from a central membrane portion 14. Asdisclosed in copending application, Ser. No. 775,729, the centralmembrane portion 14 increases endometrial surface contact, as well asprecludes bowel strangulation in the event of perforation. However, thepresent invention is not limited to the shield type of intrauterinedevice, but rather is applicable to all types of intrauterine devices,the shield type 10 only being shown and described by way of example.

Preferably, the intrauterine device.l0, as shown and preferred in theFIGURE, is a composite formed of a plastic material such as a copolymerof ethylene and vinyl acetate, polyvinyl acetate, polyethylene,polypropylene, polyvinyl chloride, nylon, or silicone rubber, such asdisclosed in co-pending patent application, Ser. No. 775,729. Mostpreferably, the plastic material is a copolymer of ethylene and vinylacetate, such as UE 632, manufactured by United States IndustrialChemical Corporation, which contains 13-15% vinyl acetate by weight. Asshown and preferred, in addition, the plastic matrix of which theintrauterine device 10 is preferably constructed, has dispersed thereinparticulate material. Most preferably, the particulate is dispersedthroughout the plastic matrix. The particulate material preferablyincludes a metal and a salt thereof, although it may comprise solely ametal or a salt. By way of example, metals which are satisfactory forpurposes of the present invention are copper, zinc, silver, platinum, orcadmium. Mostpreferably, copper particulate is preferred. By way ofexample, metal salts which are satisfactory include salts of copper,zinc, silver, platinum, or cadmium. The salt is preferably a sulfate,carbonate, nitrate, acetate or phosphate. Most preferably, the salt is asulfate of the metal particulate.

Preferably, the particulate metal in the intrauterine device composite10 is at least 0.1% by weight of the overall composite. The metal saltis, preferably, at least 0.5% by weight of the overall composite. Inaddition, the preferred overall content of metal plus metal salt in thecomposite should not exceed 50% by weight of the overall composite,thereby providing a preferred range of total particulate, by weight, inthe overall composite of between 0.1% to 50% by weight.

The requisite amount of particulate material, which is biologicallyactive, is preferably related to the water permeability or rate of watervapor transmission of the plastic matrix, which is biologically inert.The greater the permeability of the plastic, the less the requisiteamount of active particulate that need be present. Conversely, the lowerthe permeability, the greater the requisite amount of active particulatethat shouldpreferably by present. Preferably the water permeability orrate of water vapor transmission of the plastic is at least 0.3 grams/square inches/24 hours/mil at 25 C.. If desired, better results may beobtained with a water permeability of at least 5 grams/I00 squareinches/24 hours/mil at 25C.. Most preferably this rate is at least 10grams/100 square inches/24 hours/mil at 25 C..

In addition to the presence of a particulate of a metal and a saltthereof in the preferred composite, a radioopaque particulate materialmay also be dispersed therein. Preferably, this radio-opaque material isa salt of an alkaline earth metal, such as barium. Most preferably, thissalt is barium sulfate.

In order to form the intrauterine device composite, conventionaltechniques may be utilized. Once such preferred conventional techniquerequires intimately admixing particles of the desired plastic withfinely ground particulate metal and particulate metal salts at asufficiently high temperature for a sufficient time in order to obtain ahomogeneous-like phase. The resultant impregnated plastic having theparticulate material dispersed throughout is then molded under heat andpressure in a conventional manner to readily form any desiredconfiguration such as the shield configuration illustrated in theFIGURE.

The resulting intrauterine device compsite consists of a plastic matrixhaving the particulate material dispersed throughout the matrix. This isillustratively shown by the particulate, generally referred to by thereference numeral 16, shown in the FIGURE. Most preferably, theintrauterine device composite comprises a plastic matrix of a copolymerof ethylene and vinyl acetate having a particulate of copper and cupricsulfate dispersed throughout the matrix, with the percent by weight oftlie copper and cupric sulfate particulate being between 0.5% to 10% byweight of the composite, and the water permeability of the plastic beingat least 10 grams/100 square inches/24 hours/mil at 25 The presence inthe water permeable plastic matrix of the biologically active metalparticulate which preferably does not exceed an amount which degradesthe plastic matrix so as to eliminate the beneficial flexibilitythereof, assists the tensile strength, flowability for molding and otherphysical properties of the intrauterine device composite. In addition,the presence of the metal salt particulate, which is preferably a saltwhich is capable of relatively rapid ionization after insertion of theintrauterine device composite within'the uterine cavity, is believed toionize much more rapidly than the free metal particulate and causesrapid release of metal ions. When only a metal salt particulate isutilized, the ionization of the salt provides early protection, whereasprotection at a later time is provided by the chemotactic effect of theplastic matrix. Preferably, the biologically active particulate iscapable of enhancing the chemotactic effect of the otherwise relativelyinert plastic material. By virtue of the controlled release of thebiologically active particulate, relatively low concentrations thereofare capable of exerting a gameto toxic effect.

Whether the presence of the metal salt and/or metal exerts a spermicidaland/or ovacidal action or causes the tissue to react in such a manner soas to produce a material which itself is spermicidal and/or ovacidal,the presence of the metal in the ion state accelerates this action, andthe rapid ionization of the metal salt enhances this result.

By utilizing an intrauterine device composite in accordance with thepreferred embodiment of the present invention, the properties andcapabilities of an intrauterine device are markedly enhanced.

What is claimed is:

1. An intrauterine device having a body'structure encompassing an areawhich can be contained within a normal uterus, made from a compositionenabling flexing to conform to the uterine cavity comprising: a plasticmatrix, and a particulate material comprising at least one non-magneticmetal selected from a group consisting of copper, zinc, silver, platinumand cad- .mium, and at least one salt of a metal selected from saidgroup; said particulate material being dispersed within said plasticmatrix; and said particulate material comprising between 0.1% to 10% byweight of the composition of said device.

2. An intrauterine device having a composition in accordance with claim1, wherein said particulate material comprises a metal and a salt ofsaid metal.

3. An intrauterine device having a composition in accordance with claim1, wherein the material comprising said plastic matrix has a waterpermeability of at least 0.3 grams/ square inches/24 hours/mil at atemperature of 25 Centigrade.

4. An intrauterine device having a composition in accordance with claim1, wherein the material comprising said plastic matrix has a waterpermeability of at least 10 grams/ 100 square inches/24 hours/mil at atemperature of 25 Centigrade.

5. An intrauterine device having a composition in accordance with claim1, wherein said material comprising the plastic matrix is a copolymer ofethylene and a vinyl monomer material.

6. An intrauterine contraceptive device made from a composition materialas defined in claim 1 enabling flexing to conform to the uterine cavity,further comprising: a'central body having a perimeter portion with nose,tail and side portions and encompassing an area which can be containedwithin a normal uterus, and at least three spaced apart short spurs oneach of said side portions extending outwardly from said perimeterportion.

7. An intrauterine device having a composition in accordance with claim6, wherein said material comprising the plastic matrix is a copolymer ofethylene and a vinyl monomer material.

8. An intrauterine contraceptive device made from a composition materialas defined in claim 1 enabling flexing to conform to the uterine cavity,further comprising; a ring-like perimeter portion having a nose portionand opposite therefrom a tail portion with side portions joining saidnose and tail portions; and a plurality of spur-like retaining meansextending outwardly from each said side portion.

9. An intrauterine device having a composition in accordance with claim8, wherein said particulate material comprises a metal and a salt ofsaid metal.

10. An intrauterine device having a composition in accordance with claim9, wherein said material comprising the plastic matrix is a copolymer ofethylene and a vinyl monomer material.

11. An intrauterine device having a body structure encompassing an areawhich can be contained within a normal uterus, made from a compositionenabling flexing to conform to the uterine cavity comprising: a plasticmatrix, and a particulate material comprising at least copper and a saltof copper; said particulate material being dispersed within said plasticmatrix; and said particulate material comprising between 0.1% to 10% byweight of the composition of said device.

12. An intrauterine device having a composition in accordance with claim1 1; wherein said particulate material comprises copper and cupricsulfate.

13. An intrauterine device having a composition in accordance with claim12, wherein the material comprising said plastic matrix has a waterpermeability of at least 0.3 grams/100 square inches/24 hours/mil at atemperature of 25 Centigrade.

14. An intrauterine device having a composition in accordance with claim12, wherein the material comprising said plastic matrix has a waterpermeability of at least grams/ 100 square inches/24 hours/mil at atemperature of 25 Centigrade.

15. An intrauterine contraceptive device made from a compositionmaterial as defined in claim 12, enabling flexing to conform to theuterine cavity, further comprising: a central body having a perimeterportion with nose, tail and side portions and encompassing an area whichcan be contained within a normal uterus, and at least three spaced apartshort spurs on each of said side portions extending outwardly from saidperimeter portion.

16. An intrauterine contraceptive device made from a compositionmaterial as defined in claim 12, enabling flexing to conform to theuterine cavity, further comprising; a ring-like perimeter portion havinga nose portion and opposite therefrom a tail portion with side portionsjoining said nose and tail portions; and a plurality of spur-likeretaining means extending outwardly from each said side portion.

17. An intrauterine device having a body structure encompassing an areawhich can be contained within a normal uterus, made from a compositionenabling flexing to conform to the uterine cavity comprising: a plasticmatrix, and a particulate material comprising at least copper and atleast one salt of a metal selected from a group consisting of copper,zinc, silver, platinium and cadmium; said particulate material beingdispersed within said plastic matrix; and said particulate materialcomprising between 0.1% to 10% by weight of the composition of saiddevice.

2. An intrauterine device having a composition in accordance with claim1, wherein said particulate material comprises a metal and a salt ofsaid metal.
 3. An intrauterine device having a composition in accordancewith claim 1, wherein the material comprising said plastic matrix has awater permeability of at least 0.3 grams/100 square inches/24 hours/milat a temperature of 25* Centigrade.
 4. An intrauterine device having acomposition in accordance with claim 1, wherein the material comprisingsaid plastic matrix has a water permeability of at least 10 grams/100square inches/24 hours/mil at a temperature of 25* Centigrade.
 5. Anintrauterine device having a composition in accordance with claim 1,wherein said material comprising the plastic matrix is a copolymer ofethylene and a vinyl monomer material.
 6. An intrauterine contraceptivedevice made from a composition material as defined in claim 1 enablingflexing to conform to the uterine cavity, further comprising: a centralbody having a perimeter portion with nose, tail and side portions andencompassing an area which can be contained within a normal uterus, andat least three spaced apart short spurs on each of said side portionsextending outwardly from said perimeter portion.
 7. An intrauterinedevice having a composition in accordance with claim 6, wherein saidmaterial comprising the plastic matrix is a copolymer of ethylene and avinyl monomer material.
 8. An intrauterine contraceptive device madefrom a composition material as defined in claim 1 enabling flexing toconform to the uterine cavity, further comprising; a ring-like perimeterportion having a nose portion and opposite therefrom a tail portion withside portions joining said nose and tail portions; and a plurality ofspur-like retaining means extending outwardly from each said sideportion.
 9. An intrauterine device having a composition in accordancewith claim 8, wherein said particulate material comprises a metal and asalt of said metal.
 10. An intrauterine device having a composition inaccordance with claim 9, wherein said material comprising the plasticmatrix is a copolymer of ethylene and a vinyl monomer material.
 11. Anintrauterine device having a body structure encompassing an area whichcan be contained within a normal uterus, made from a compositionenabling flexing to conform to the uterine cavity comprising: a plasticmatrix, and a particulate material comprising at least copper and a saltof copper; said particulate material being dispersed within said plasticmatrix; and said particulate material comprising between 0.1% to 10% byweight of the composition of said device.
 12. An intrauterine devicehaving a composition in accordance with claim 11; wherein saidparticulate material comprises copper and cupric sulfate.
 13. Anintrauterine device having a composition in accordance with claim 12,wherein the material comprising said plastic matrix has a waterpermeability of at least 0.3 grams/100 square inches/24 hours/mil at atemperature of 25* Centigrade.
 14. An intrauterine device having acomposition in accordance with claim 12, wherein the material comprisingsaid plastic matrix has a water permeability of at least 10 grams/100square inches/24 hours/mil at a temperature of 25* Centigrade.
 15. Anintrauterine contraceptive device made from a composition material asdefined in claim 12, enabling flexing to conform to the uterine cavity,further comprising: a central body having a perimeter portion with nose,tail and side portions and encompassing an area which can be containedwithin a normal uterus, and at least three spaced apart short spurs oneach of said side portions extending outwardly from sAid perimeterportion.
 16. An intrauterine contraceptive device made from acomposition material as defined in claim 12, enabling flexing to conformto the uterine cavity, further comprising; a ring-like perimeter portionhaving a nose portion and opposite therefrom a tail portion with sideportions joining said nose and tail portions; and a plurality ofspur-like retaining means extending outwardly from each said sideportion.
 17. An intrauterine device having a body structure encompassingan area which can be contained within a normal uterus, made from acomposition enabling flexing to conform to the uterine cavitycomprising: a plastic matrix, and a particulate material comprising atleast copper and at least one salt of a metal selected from a groupconsisting of copper, zinc, silver, platinium and cadmium; saidparticulate material being dispersed within said plastic matrix; andsaid particulate material comprising between 0.1% to 10% by weight ofthe composition of said device.